Disc drive assembly with improved communications and reduced contamination risk

Abstract

A disc drive assembly includes a brushless direct current drive motor having a stationary shaft and a hub rotatably mounted about the stationary shaft by upper and lower bearings. The hub includes an interior space for housing a stator which has magnetically active parts for magnetic interaction with a permanent magnet mounted on an inner surface of the hub. The brushless drive motor is releasably mounted on a disc drive base member having a centrally located boss. The boss cooperates with a lower surface of a stator support for maintaining the stator of the drive motor in spaced relation with respect to the disc drive base member so that a printed circuit connector may be disposed between the stator and the disc drive base member proximate the stator winding. The subject invention also includes a labyrinth seal in combination with a ferrofluidic seal to prevent contaminant particles generated by the bearings and other internal parts of the drive motor from escaping into a contaminant-free disc storage environment.

What is claimed is: 
     
       1. A disc drive assembly for receiving at least one storage disc in a contaminant-free environment, said disc drive assembly comprising: a brushless drive motor having a stationary shaft and a hub mounted about said stationary shaft, said hub including an interior space for receiving a stator therein, said stator having winding means and magnetically active parts including a stator stack lamination for magnetic interaction with a permanent magnet mounted on an inner surface of said hub, said brushless drive motor further including means for mounting said stator to said stationary shaft and for supporting said stator in a generally fixed position relative to said hub, said hub rotatably mounted to said stationary shaft by upper and lower bearing means, each of said upper and lower bearing means having an inner race mounted to said stationary shaft and an outer race mounted to said hub, said hub having a shoulder means for supporting said at least one storage disc in said combustion-free environment; and   a disc drive base member for mounting said brushless drive motor thereon, said disc drive base member including a boss for receiving an end of said stationary shaft of said brushless drive motor, said stationary shaft including threaded connecting means for releasably securing said stationary shaft to said disc drive base member through an aperture in said boss, said boss cooperating with a lower surface of said stator mounting and supporting means for maintaining said stator of said brushless drive motor in spaced relation with respect to said disc drive base member so that a printed circuit connector may be disposed between said stator and said disc drive base member proximate said winding means for permitting electronic communication between said winding means and the associated printed circuitry from an external controller.   
     
     
       2. A disc drive assembly as defined in claim 1 wherein said threaded connecting means of said stationary shaft operably engages mating threaded connecting means of a nut to releasably secure said stationary shaft to said disc drive base member. 
     
     
       3. A disc drive assembly as defined in claim 1 wherein said printed circuit connector comprises: an annular portion at one end for mounting said printed circuit connector around said boss.   
     
     
       4. A disc drive assembly as defined in claim 1 further comprising: a labyrinth seal defined by an inner surface of said hub, an outer surface of said stator, and an upper surface of said stator mounting and supporting means to prevent contaminant particles generated by said upper and lower bearing means or other internal parts of said brushless drive motor from escaping into said contaminant-free environment.   
     
     
       5. A disc drive assembly as defined in claim 1 further comprising: a ferrofluidic seal disposed above said upper bearing means and between said hub and said stationary shaft to prevent airborne contaminant particles generated by said upper bearing means or other internal parts of said brushless drive motor from escaping into said contaminant-free environment.   
     
     
       6. A disc drive assembly as defined in claim 1 wherein: said hub being formed in a generally inverted U-shape in cross-section, said hub having an upper surface, an inner annular arm mounted to said outer race of said upper and lower bearing means, and an outer annular arm for carrying said permanent magnet.   
     
     
       7. A disc drive assembly as defined in claim 6 wherein said outer annular arm carries said shoulder means. 
     
     
       8. A disc drive assembly for receiving at least one storage disc in a contaminant-free environment, said disc drive assembly comprising: a brushless drive motor having a stationary shaft and a hub mounted about said stationary shaft, said hub including an interior space for receiving a stator therein, said stator having winding means and magnetically active parts including a stator stack lamination for magnetic interaction with a permanent magnet mounted on an inner surface of said hub, said brushless drive motor further including means for mounting said stator to said stationary shaft and for supporting said stator in a generally fixed position relative to said hub, said hub rotatably mounted to said stationary shaft by upper and lower bearing means, each of said upper and lower bearing means having an inner race mounted to said stationary shaft and an outer race mounted to said hub, said hub having a shoulder for positioning said at least one storage disc in said contaminant-free environment;   a labyrinth seal defined by an inner surface of said hub, an outer surface of said stator, and an upper surface of said stator mounting and supporting means to prevent contaminant particles generated by said upper and lower bearing means or other internal parts of said brushless drive motor from escaping into said contaminant-free environment;   a ferrofluidic seal disposed above said upper bearing means and between said hub and said stationary shaft to prevent airborne contaminant particles generated by said upper bearing means or other internal pats of said brushless drive motor from escaping into said contaminant-free environment; and   a disc drive base member for mounting said brushless drive motor thereon, said disc drive base member including a boss for receiving an end of said stationary shaft of said brushless drive motor, said stationary shaft including threaded connecting means for releasably securing said stationary shaft to said disc drive base member through an aperture in said boss, said boss cooperating with a lower surface of said stator mounting and supporting means for maintaining said stator of said brushless drive motor in spaced relation with respect to said disc drive base member so that a printed circuit connector may be disposed between said stator and said disc drive base member proximate said winding means for permitting electronic communication between said magnetically active winding means and the associated printed circuitry from an external controller.